The prior art is already aware of collet clamping and releasing devices such as those shown in U.S. Pat. Nos. 2,393,458 and 3,087,736 and 3,791,661. Also, devices for actuating a clamping chuck or vise jaw are shown in U.S. Pat. Nos. 809,296 and 2,479,973 and 3,306,604.
Still further, the prior art is already aware of devices where a plurality of collets or chucks are operative within a single mounting block, such as shown in U.S. Pat. Nos. 3,632,122 and 4,614,469.
The present invention improves upon the prior art in that it utilizes a yoke which snugly engages an axially movable sleeve surrounding the collet, and thereby providing for quick and precise retention of the collet which is holding the workpiece itself. In this arrangement, the yoke engages the sleeve on three sides of the sleeve to thereby retain the sleeve in an aligned position and against a rotation, even though the sleeve itself may have slight clearance relative to the block in which it is mounted. Therefore, the collet itself is locked evenly in place, even though there may be slight clearance with respect to the sleeve. Further, with the yoke preventing sleeve rotation, the collet and sleeve are readily non-rotatably related so therefore the collet itself cannot rotate. For precision workmanship, it is critical that the collet does not have any radial play or movement of any sort, and the yoke employed in this invention assures the desired precision.
Still further, the present invention is an improvement in that the collet locking actuator is enclosed entirely within the support block itself, so there is no interference with the tooling which is applied to the workpiece, and the entire collet supporting apparatus is therefore arranged with no protruding parts which could interfere with the use of the apparatus. Also, the actuator is operative, at least in one embodiment herein, by means of standard wrenches, either manual or powered wrenches. In that embodiment, the apparatus does not depend upon return springs or the like for release of the collet, but instead the collet is positively released manually.
This invention accomplishes the aforementioned and does so by means of a collet retainer which is connected with the mounting block itself so that the collet and its retainer are always available and in position, and thus when the collet is in the released position it is still supported on the mounting block and will not have to be readjusted nor will it become disassembled and possibly lost.
The arrangement herein also permits the workpieces to be loaded from either axial end of the collet, and the collets can also be closely based relative to each other so that there is only a minimum of tool travel for working on a plurality of the collets supported in one common work block. This also provides for a saving of space, as well as efficiency in the tooling action, and thus idle time is held to a minimum. Also, a single fastener, such as a nut, is employed in the connected position relative to the support block, and that single nut is always available on the support block for receiving and fastening to a selected variety of collets, and thereby promoting the changing of collets for desired sizes and the like.
Still further, workpiece stops can be readily mounted on the support blocks to be adjustably positioned in alignment with the workpiece for stopping the workpiece in the desired position for clamping in the collet. The stops employed herein also do not interfere with the movement or dispensing of chips or other debris which can actually move through the collet itself and away from the entire apparatus.
In all of these instances, the present invention can utilize the standard type of collet, and no specially designed collet is required, and the collet fastener, or nut, is employed for the customary holding of the standard collet, but, in the present instance, as mentioned above, the fastener or nut in this invention is retained with the support block and cannot be removed from the support block, except for an intentional disassembly of the nut relative to the block, and that entails more than simply unthreading the nut relative to the block such as might be done in U.S. Pat. No. 2,393,458, for instance.
Accordingly, the present invention provides for a collet actuator which may be either manual or power actuated, and it may be either a single mounted collet or a plurality of collets in a single support block, and, in any instance mentioned, the workpiece is held to a high standard of precision by virtue of the yoke surrounding the movable sleeve acting upon the collet itself.